The field of the present invention is lighting systems for outdoor lighting purposes.
Outdoor lighting systems have an infinite number of applications for outdoor illumination. Such systems are used to illuminate and thus to enhance the effects of flagpoles, signs, shrubbery and other architectural focal points. Outdoor lighting can provide general flood lighting to areas for security purposes and also provide spot lighting where desired.
The placement and location of conventional lighting systems for outdoor lighting is severely restricted. Conventional systems are especially vulnerable to the destructive effects of corrosive soils, thus an above grade placement is normally required. Such a placement can detract from the aesthetics of the lighted area and can restrict the utility of such systems. Also, such conventional systems are not designed to handle human foot traffic, thus placement of conventional systems is further restricted. Conventional systems are also vulnerable to moisture and water intrusion.
To overcome these difficulties, outdoor lighting systems have been developed which employ a fully sealed system of structural material. Conventional systems cannot tolerate water entry into the housing, so an open housing allowing air and water to flow therethrough cannot be used for cooling the lamp. Any moisture entry into such systems has the potential to cause a shorting out of the electrical system and rapid corrosion. Thus, outdoor systems have required sealing. Because of requirements to completely seal the outdoor systems, such devices are expensive, difficult to repair and difficult to cool. The poor thermodynamic characteristics dictate size and limit light output. The use of thick materials such as lenses and housings can also add to the cooling problem.
The design of conventional outdoor systems can make them difficult to relamp; and field personnel can encounter several obstacles when attempting to repair such systems. Numerous fasteners are typically used in sealing these systems. The reliance on such fasteners can make removal of the lamp difficult and repeated working of the fasteners can deteriorate their performance and eventually affect the integrity of the seal. Field repairs can trap humidity in the lamp, which eventually condenses inside the lamp and has the potential to short out and/or corrode the electrical system. Such cyclical intrusion causes conventional systems to have a very high cost of repair and maintenance with limited utility.